Search results for "Karst"

Evaporitic karst in Sicily

2005

First study of gypsum karst in Sicily. The contribution of Olinto Marinelli and Mariano Gemmellaro

2006

Karst, acantilados y calas en el Migjorn de Menorca

2017

[spa]La costa sur de la isla de Menorca se caracteriza por la presencia, de forma más o menos continua, de acantilados verticales cortados en los depósitos carbonatados que constituyen una plataforma atribuida al Mioceno superior. Los acantilados se encuentran interrumpidos en la zona litoral por una marcada incisión producida por los barrancos que drenan toda la plataforma miocena del sur de la isla y que, en su desembocadura al mar, dan lugar a las denominadas calas. La forma de éstas viene controlada no tan sólo por la fracturación, que a su vez controla la red de drenaje, sino que también por la contribución de los procesos kársticos que están directamente relacionados con la …

Coprolites in natural traps : direct evidence of bone-eating carnivorans from the Late Miocene Batallones-3 site, Madrid, Spain

2021

We describe two carnivoran coprolites found in the pseudokarst natural carnivore trap of Batallones-3, from the Late Miocene of Spain. The larger one, comprising multiple indistinguishable fragments of broken and corroded bones, indicates that the producer of the dropping might have been highly capable of crushing the softer parts of large bones. On the other hand, the smaller one shows several relatively larger and more complete bone fragments, thus exhibiting a greater capacity to break and swallow large portions of bone. The external morphology of the large coprolite is similar to that of extant bears, whereas the smaller one more closely resembles that of the living insectivorous hyaeni…

A stalactite record of four relative sea-level highstands during the Middle Pleistocene Transition

2017

International audience; Ice-sheet and sea-level fluctuations during the Early and Middle Pleistocene are as yet poorly understood. A stalactite from a karst cave in North West Sicily (Italy) provides the first evidence of four marine inundations that correspond to relative sea-level highstands at the time of the Middle Pleistocene Transition. The speleothem is located ∼97 m above mean sea level as result of Quaternary uplift. Its section reveals three marine hiatuses and a coral overgrowth that fixes the age of final marine ingression at 1.124 ± 0.2, thus making this speleothem the oldest stalactite with marine hiatuses ever studied to date. Scleractinian coral species witness light-limited…

Upper pleistocene interstratal piping-cave speleogenesis: The seso cave system (central pyrenees, northern spain)

2015

The Seso Cave System (SCS, South Central Pyrenees, Northeastern Spain) develops in poorly soluble marly interstratum between limestone beds of Eocene age. We propose an innovative and singular pseudokarstic speleogenetic model under vadose conditions based on cave morphological evidence, physicochemical and mineralogical characteristics of the Eocene marly host rock, U-Th dating of cave deposits, and local geological and geomorphological information. Eocene marls are shown to be sensitive to dispersion processes supported by their high clay content and the high concentration of sodium and low electrical conductivity in the seepage water. Runoff inside the cave results from water that infilt…

Zvaigžņotā Debess: 2010, Rudens (209)

2010

Contents: G.Carevsky, I.Daube. Comet Bennett ; E.Fogels. Srinivasa Ramanujan ; M.Krastiņš. Smallest Planet of the Solar System: a Riddle of Centuries (1st part) ; A.Alksnis, Z.Alksne. Hot Jupiters and Their Retrograde Motion ; V.Karitāns. James Webb Space Telescope. What will it Be? ; K.Salmiņš. GFZ CHAMP Laser Tracking Award to SLR Station Riga ; J.Jansons. Vladimir Afanasjev, Officer of the Baikonur Cosmodrom in the 1970s (concluded) ; J.Limansky. International Year of Astronomy 2009 in Philately. Series EUROPA (2nd sequel) ; J.Dambītis. Centenary of Prominent Latvian Mathematician Ernests Fogels (1910-1985) ; J.Klētnieks. Sketches of History of Astronomy (concluded) ; M.Gills. Public Sun…

Cerro del Hierro, Spain: the largest exposed early Cambrian palaeokarst

2020

AbstractWe study the largest exposed example of an early Cambrian palaeokarst, associated with laterites and developed during rifting of the Ossa–Morena Zone. The lithostratigraphy, biostratigraphy, facies and the genesis reflect episodes of sea-level fall (Cerro del Hierro Regression) related to tectonic events and palaeoclimate. This palaeokarst can be primarily considered as the result of early Cambrian polyphase karstification in an extensional tectonic regime, later modified by Neogene–Quaternary geomorphological processes. The event may correlate with other regressive events of a similar age in Spain, Italy, United Kingdom, South America and Australia. This episode also has local name…

Geomorphology of the Capo San Vito Peninsula (NW Sicily): An Example of Tectonically and Climatically Controlled Landscape

2017

The Capo San Vito peninsula is located along the north-westernmost sector of the Sicilian coastline. It is characterized by a complex geomorphological setting, where a large variety of coastal, gravity-induced and karst landforms allow the visitor to easily detect the interactions between Quaternary tectonics and climate changes as well as morphodynamic processes responsible for shaping the landscape. Thanks to natural reserves, the peninsula preserves a typical Mediterranean natural environment, marked by spectacular and suggestive landforms.

Impact of Rocky Desertification Control on Soil Bacterial Community in Karst Graben Basin, Southwestern China

2021

Microorganisms play critical roles in belowground ecosystems, and karst rocky desertification (KRD) control affects edaphic properties and vegetation coverage. However, the relationship between KRD control and soil bacterial communities remains unclear. 16S rRNA gene next-generation sequencing was used to investigate soil bacterial community structure, composition, diversity, and co-occurrence network from five ecological types in KRD control area. Moreover, soil physical-chemical properties and soil stoichiometry characteristics of carbon, nitrogen and phosphorus were analyzed. Soil N and P co-limitation decreased in the contribution of the promotion of KRD control on edaphic properties. T…